Myobloc

Myobloc, which is also known as botulinum toxin type B, comes from the bacteria that causes botulism. Botulinum toxin stops nerve activity in the muscles, leading to a temporary decrease in muscle activity.

Myobloc is used in adults to treat abnormal head position and neck pain caused by cervical dystonia.

Myobloc is also used in adults to treat chronic drooling (sialorrhea).

Myobloc may also be used for reasons that are not mentioned in this medication guide.

The botulinum toxin in Myobloc can move to other parts of the body beyond where it was injected. This can lead to serious life-threatening side effects.

Contact your doctor immediately if you experience a hoarse voice, droopy eyelids, vision issues, severe muscle weakness, loss of bladder control, or difficulty breathing, talking, or swallowing. Some of these effects may happen up to several weeks after a botulinum toxin injection.

You should not be treated with Myobloc if you are allergic to it or any other botulinum toxin injection, such as onabotulinumtoxinA, abobotulinumtoxinA, or incobotulinumtoxinA, or if you have an infection in the area where the medicine will be injected.

Tell your doctor if you have ever had a side effect after receiving a botulinum toxin.

Tell your doctor if you have or have ever had:

• a nerve-muscle disorder, such as myasthenia gravis, ALS (Lou Gehrig's disease), or Lambert-Eaton syndrome;
• a breathing disorder or problems such as asthma or emphysema;
• droopy eyelids;
• problems with swallowing;
• bleeding problems;
• surgery on your face;
• a planned surgery; or
• received other botulinum toxin injection in the past 4 months.

Myobloc is made from donated human plasma and may contain viruses or other infectious agents. Donated plasma is tested and treated to reduce the risk of contamination, but there is still a small possibility it could transmit disease. Ask your doctor about any possible risk.

It is not known if Myobloc will harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant.

Ask a doctor if it is safe to breastfeed while using Myobloc.

Get emergency medical help if you have signs of an allergic reaction: hives, difficult breathing, swelling of your face, lips, tongue, or throat.

The botulinum toxin in Myobloc can spread to other parts of the body beyond where it was injected. This has caused side effects in some people after receiving botulinum toxin injections, even for cosmetic reasons. Problems with swallowing and breathing can be very serious and life-threatening, especially in children with certain muscle issues.

Call your doctor immediately if you experience any of these side effects (up to several hours or weeks after an injection):

• unusual or severe muscle weakness (especially in a body area that was not injected with the medication);
• trouble breathing, talking, or swallowing;
• hoarse voice, droopy eyelids, blurred vision, double vision, or other vision problems; or
• loss of bladder control.

Common side effects of Myobloc may include:

• pain or discomfort at the injection site;
• headache;
• dry mouth; or
• trouble swallowing.

This is not a complete list of side effects and others may happen. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Myobloc is injected into a muscle or into a gland by a healthcare provider. Your doctor will determine when to receive the next dose.

Your injections may be given into more than one area at a time, depending on the condition being treated.

Your doctor may occasionally change your dose until your doctor determines the best dose.

Your doctor may need to check your progress on a regular basis, and your next dose may change based on your response to treatment.

Call your doctor if your symptoms do not improve, or if they get worse.

Do not receive botulinum toxin injections from more than one medical professional at a time. If you switch healthcare providers, be sure to tell your new provider how long it has been since your last botulinum toxin injection.

Using this medicine more often than prescribed will not make it more effective and may result in serious side effects.

Call your doctor for instructions if you miss your appointment for Myobloc.

Seek emergency medical help or call the Poison Help line at 1-800-222-1222.

Symptoms of an overdose may not show up immediately, but they can include muscle weakness, difficulty swallowing, weak or shallow breathing, or loss of movement in any part of your body.

Myobloc may slow your reactions and can cause weakness, loss of strength, or changes in vision. Do not drive or engage in hazardous activities until you know how Myobloc will affect you.

Tell your doctor about all your other medicines, especially:

• a muscle relaxer;
• an injectable antibiotic;
• sleep medicine;
• botulinum toxin such as Dysport, Xeomin, Botox, Botox cosmetic;
• cold or allergy medicine (Benadryl and others);
• medicine to treat Parkinson's disease;
• medicine to treat stomach problems, motion sickness, or irritable bowel syndrome;
• medicine to treat overactive bladder; or
• bronchodilator asthma medication.

This list is not complete and many other drugs may affect Myobloc. This includes prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible drug interactions are listed here.

• What is botulinum toxin used to treat?